A raid near Warwick on Wednesday uncovered hundreds of thousands of dollars in cash, and 30kg of cannabis with a street value of up to $500,000.

Massie man Thomas Edward Martin, a long-term associate of Mr O'Dempsey, was charged with alleged drug trafficking and possession offences and is being remanded in custody ahead of a court appearance tomorrow.

The Queensland Police homicide cold case unit's Detective Inspector Mick Dowie said on Thursday Mr O'Dempsey had been a person of interest in the McCulkin investigation since it began.